Wellhead connector



Dec. 2 9, 1964 R. J. BAUER ETAL WELLHEAD CONNECTOR Filed July 26, 1961 3Sheets-Sheet 1 INVENTORS= R. J. BAUER .1. A. HAEBER L.G. OTTEMAN FIG-lR.F. PERNER THEIR AGENT Dec. 29, 1964 R. J. BAUER ETAL 3,163,223

WELLHEAD CONNECTOR Filed July 26, 1961 3 Sheets-Sheet 2 FIG. 3

INVENTORS:

R. J. BAUER J.A. HAEBER L.G. OTTEMAN R.F. PERNER BY; H .16 EIR AGENTDec. 29, 1964 R. J. BAUER ETAL 3,153,223

WELLHEAD CONNECTOR Filed July 26, 1961 3 Sheets-Sheet 3 THEIR AGENTUnited rates Patented Dec. 29, 1964 3,163,223 WELLHEAD CONNECTOR RichardJ. Bauer, Westport, Conn, John A. Haeher and Lloyd G. Utteman, Houston,Ten, and Raymond F. Perner, Metairie, Ln, assignors to Shell GilCompany,

New York, N.Y., a corporation of Delaware Filed July 26, E63, Ser. No.127,954

4 Claims. Zl. 166-665) This invention relates to apparatus for use onoffshore wells and pertains more particularly to a wellhead apparatusadapted to be securely locked on a well casinghead positionedunderwater. The present invention is especially concerned with apparatusfor connecting a wellhead component, such for example as a blowoutpreventer, to a vertically-extending wellhead component in a securelylocked and fluidtight manner so that the wellhead component could not heaccidentally separated from the vertically-extending well member.

*In an attempt to locate new oil fields, an increasing amount of welldrilling has been conducted at offshore locations, such for example, asoff the coast of Louisiana, Texas and California. As a general rule, thestrings of casing in a well together with the tubing string or stringsextend .to a point well above the surface of the water where they areclosed in the conventional manner that is used on land wells, with aconventional wellhead assembly eing attached to the top of the casing.Attempts have been recently made to provide methods and apparatus fordrilling and completing a well wherein both the well casinghead andsubsequently .the wellhead assembly and casinghead closure device arelocated underwater at a depth sufiicient to allow ships to pass overthem. Preferably, the casinghead and wellhead closure assemblies arelocated close to the ocean floor. In order to install equipment of thistype underwater in depths greater than the shallow depth at'which adiver can easily operate, it has been necessary to design entirely newequipment for this purpose. Thus, when drilling and completing an oil orgas well at an offshore location in a manner described in copendingpatent application, Serial No. 830,538, filed July 30, 1959, andentitled Underwater Well Completion Method, the well casinghead may haveattached thereto various pieces of equipment by means of the apparatusof the present invention.

It is therefore a primary object of the present invention to provideapparatus for connecting a wellhead component to an underwater wellheadassembly while operating the apparatus from a remote location.

It is another object of the present invention to provide a wellhead suchas a blowout preventer with a connector device so that the blowoutpreventer may be lowered on guide lines and seated on an underwater wellcasinghead and securely locked thereto in a fluidtight manner with thesea-ling and locking operations being carried out from a remotelocation.

-A further object of the present invention is to provide,

a remotely operable connector apparatus adapted to lock on to anunderwater wellhead and pack oh the annulus between the connector deviceand the wellhead.

Another object of the present invention is to provide aremotely-controlled hydraulically-operated connector device and sealingapparatus for holding a wellhead component on a wellhead againstpressures which might be encountered therein at any time, even in theevent that the hydraulic pressure lines to said apparatus should break,or otherwise become inoperative. V

A still further object of the present invention is to provide a wellheadconnector device and sealing apparatus which may readily be unlockedfrom an underwater .wellhead and withdrawn to an operational base at thesurface, such for example to a drilling barge or platform.

' in FIGURE 1 as comprising a base member 21 which is Another object ofthe present invention is to provide a wellhead connector device adaptedto seat on an underwater wellhead and be connected to the insidethereof,-

rather than the outside thereof, so that the seating and latchingsurfaces of a well casinghead are isolated in a manner such that theyare protected from corrosion, from sea water and from marine growth thatwould prevent a tool being telescoped over a well casinghead and latchedthereon. 7

These and other objects of this invention will be understood from thefollowing description taken with reference to the drawing, wherein:

FIGURE l is a diagrammatic view illustrating a floatable drilling bargepositioned on the surface of the ocean from which a blowout preventertogether with the connector device of the present invention is beinglowered to the top of a well casinghead positioned on the ocean floor;and

FEGURES 2, 3 and 4 are views taken in longitudinal cross-section ofseveral forms of a wellhead connector illustrated as being positioned ina vertically-extending well member in its sealed and latched position.

Referring to FIGURE 1 of the drawing, a drilling barge 1-1, of anysuitable floatable type is illustrated as floating on the surface of thewater 12 and fixedly positioned over a preselected drilling location bybeing anchored to the ocean fioor 13 by suitable anchors (not shown);Equipment of this type may be used when carrying on Well drillingoperations in water depths varying from about to 1500 feet or more. Thedrilling barge is equipped with a suitable derrick 16 and a rotary table17 as well as other auxiliary equipment needed during the drilling of awell.- The derrick '16 is positioned over a drilling slot or well 18which extends vertically through the barge in a conventional manner.When using the equipment of the present invention the slot '18 and thebarge l l maybe either centrally located or extend in from one edge.However, drilling operations may be carried out over the side of thebarge without the use: of 'a slot. Additionally, it is to be understoodthat the equipment of the present invention may also be used whiledrilling a well from any suitable operational base positioned above thesurface of a body of water, such for example as from a drilling bargehaving feet extending to the ocean floor, or :from a platformpermanently positioned on the ocean floor.

A typical underwater wellhead structure is illustrated positioned on theocean floor 113 and is fixedly secured to a conductor pipe orlarge-diameter well casing 22 which extends down into a well, which hasbeen previously drilled, and is cemented therein. Thus, the basestructure Ed is rigidly secured to the ocean floor in order to supporttwo or more vertically-extending guide columns 23 and 24 adapted toreceive and guide therein arms 25 and 26 which are arranged to slidealong vertically-extending guide cables 27 and 28. The lower ends of theguide cables 27 and 23 are anchored to the base structure 21 within theguide columns v2?; and 24 while extending upwardly through the water tothe drilling barge 11 where they are preferably secured to constanttension hoists 31 and 32.

Centrally positioned above the base plate 21 and fixedly securedthereto, or to the conductor pipe 22, is a well more grooves, and extendaround the inner wall of the casinghead. The wellhead is also shown asbeing provided with a cement circulation or kill line 36 which isconnected preferably by means of a quick-disconnect coupling 37'to aflow-control valve 38.

FIGURE 1 the wellhead connector'41 is shown as it is being lowered intothe top of the casinghead 33. The combined blowout preventer andwellhead connectorl) and 41, respectively, are run into positionon thetop'of the well by being lowered through the water from the barge 11 bymeans of a pipe string 42, commonly known as a running string, theblowout preventer 40 being connected to the lower end of the runningstring 42 by means of a suitable coupling or connector 43 which may takethe form of the wellhead connector 41. The valve 38, connector 41,blowout preventer 40 and connector .3 are all hydraulically operated andare provided with hydraulic flowlines 44 and 45, 46 and 47, 48 and 4?,and 50 and 51, respectively. 'These fiowlines, 44 through 51, extend up-.wardly from the wellhead equipment to the barge 11 where theyareconnected to a suitable source of pressure fluid.

Referring to FIGURE 2 of the drawing, the wellhead connector 41 isillustrated as being seated'in the casinghead 33. A seal 54 may beprovided at the top of the casinghead 33 to seal the space between thetop, of the casinghead 33 and the flange 55by which the wellheadconventer4 (FIGURE 1). the sea water out of the apparatus.

The sealing element 54keeps Thebody of the wellhead connector,preferably near the lower end thereof, is provided with a shoulder.seating'surface d adapted to itself may seat directly on the top of thecasinghead 33'."

An annular seal 58 is preferably carried on the outersurface of thewellhead'connector 41 and is expandable .nector 41 is secured to thebottom 'of the blowout pre-,

throughconduits 47 and 62 to force the piston upwardly to the top of thechamber 61. The wellhead connector is provided with a vertical bore 72through which drilling'oper-ations may be carried out, or equipment runinto the well.

Another form of the present wellhead connector is illustrated in FIGURE3. This arrangement ditfers from that described with regard to FIGURE 2in that the dogs 64- are positioned above the annular seal 58, and thepiston 59 has a single camming face 66 which is adapted to actuatesequentially both the locking dogs 64v and the annular seal 58.

A third modification of the wellhead connector of the present inventionis illustrated in FIGURE 4. In this embodiment, an annular seal 75 isprovided which is expanded against the inner wall of the casinghead 33when the lower end of the wellhead connector 41a, which is slidablymounted on a reduced diameter portion 41b of the wellhead connector 41,is forced upwardly. A suitable stop member 76 or anchoring ring 'isprovided on the outer surface of the lower end portion 41b of thewellhead connector 41 for preventing the slidable portion 41a fromdropping off as the apparatus is inserted into a casinghead. If desired,additional seals 77 and 78 may be provided in thevertical wallin theseating shoulder of slidable element 41a. 7

While the blowout preventer 46 (FIGURE 1) of the present invention'hasbeen described with regard to having a wellhead connector 41 secured tothe lower end thereof for locking the blowout preventer into the top ofa well 7 casinghead, it is to be understood that the blowout p're:venter could have a similar wellhead connector 41a (FIG- URE 5)extendingupwardly therefrom to receive and against. the inner surface ofthe casinghead 33 by means I of a tubular-shaped piston element 5 9; Thepiston 59 is slidably mounted within an annular chamber 61. A 'pair ofconduits 62 and '63 extend through the .W8llh63d C0I1 nectorl and are incommunication with the upper and lower ends of the. chamber 61.

The wellhead connector 41 is also provided with a series ofoutwardly-extendible locking dogs 64 which are adapted to be forcedoutwardly into one or more annular grooves 65, cut in the inner face ofthe casinghead 33, upon downwardly movement of the piston 59. The pistonelement 59 is provided with a downwardly and inwardly sloping face 66which forcesthe dogs 64 into their locking 5 position. The outer upperedge of the locking dogs 64 are preferably bevelled, as at 67, so thatthe dogs 64 are readily retracted into the wellhead connector 41 upon anupward pull of the wellhead connector 41 with respect to the casinghead33, after the piston element 59 has been raised'to its uppermostposition. .Although the carnming surface 66 of the piston 59 can .beutilized to actuate sequentially first the annular seal 58 and then thelocking 7 dogs 64, the piston 59 is preferably provided with a seconddownwardly and inwardly sloping'face 68 spaced above face'ti a'suitabledistance so that the seal'58 and the lock- 1 ing dogs'fi laresimultaneously actuated. By using two camming surfaces 6 6 and 68, thestroke of the piston.59 can be materially shortened. Y

j In order tooperate the locking dogs 64 of the present apparatus, it isnecessary that a pressure fluid be supplied 1 from the barge 11(FIGURE 1) down through conduit 46 whichis in communication with conduit63 (FIGURE'Z) of thewellhead connector 41. The pressure fluid'forcespiston 5% downwardly, which in turn actuates the seal 58 and thelockingdogs 64. The locking dogs 64 are premitted to extend outwardly adistance equal'to the width 1 of a vertical slot 70 in each dog, minusthediam ete'r of a retaining pin 71; which prevents the dog64 fromfalling oittjof the apparatus. To unlock the dogs and unsealthe wellheadconnector, pressure fluid would be supplied lock thereon the lower endof a large diameter pipestring or marine conductor 89 which would extendfrom the wellhead to a point above the surface of the water, as toabarge. Use of a second wellhead connector at the top of :a blowoutpreventer which was already positioned in a well, would greatly simplifyrunning additional pipe member, a blowout preventer lock-down apparatusse' cured to at least one end of said blowout preventer coaxialtherewith, said lock-down apparatus comprising a cylindrical body memberhaving an axial bore therethrough and being of a size-to fitinto theopen upper. end of, said vertically projecting tubular well member,outwardly extending shoulder means formed on the outside of said bodymember, said shoulder means having a diameter greater than that of atleast a portion of the bore of said tubular well member in which itfits,locking means movablytcarried by said body member and being bodilymovable outwardly thereofiso that a: portion of said lock-- ing meansprojects beyond the surface of saidbody meme berrtoward; and intocontact with seating. groove. means in the inner surface of said wellmember, annular seal means carried outwardly on said body memberadapted" to form a fluidtight seal with asurrounding well member,

and actuating means carried by .said body member foroperatively'engaging said locking means, said actuating means beingmovable'with respect to saidbody member in response to fluid pressureapplication thereto to move,

said locking means outwardly of saidbody member into 'locklng'positionwith a surrounding well member thereby preventing separation of saidbody member and said well 7 member; said apparatus containing pressurefluid port 1 to the bottom of the piston 59 means in fluid communicationon one end with the actuating means in said body member with the otherend extending through the wall of said body member and adapted tocommunicate with a source of pressure fluid.

2. An apparatus for facilitating underwater wellhead operations which inassembly comprises a vertically projecting tubular well member, ablowout preventer adapted to be mounted on the upper end'of said tubularwell member, a blowout preventer lock-down apparatus secured to at leastone end of said blowout preventer coaxial therewith, said lock-downapparatus comprising a cylindrical two-piece body member having upperand lower portions with an axial bore therethroughand being of a size tofit into the open upper end of said vertically projecting tubular wellmember, the upper portion of said body member having a downwardlyextending tubular element, the .lower portion of said body member beingmounted on said downwardly extending tubular element for limited axialslidable movement relative to said upper portion, an annular resilientseal carriedby said body member between the upper and lower portionsthereof, said seal being of a diameter to project beyond the outersurface of said body member when compressed between said upper and lowerportions thereof, outwardly extending shoulder means formed on theoutside of the lower portion of said body member, said shoulder meanshaving a diameter greater than that of at least a portion of the bore ofsaid tubular well member in which it fits, locking means carried by saidbody member and being bodily movable outwardly thereof so that a portionof said locking means projects beyond the surface of said body membertoward and into. contact with seating groove means in inner surface ofsaid well member, and actuating means carried by said body member foroperatively engaging said locking means, said actuating means beingmovable with respect to said body member in response to fluid pressureapplication thereto to move said locking means outwardly of said bodymember into locking position with a surrounding well member therebypreventing separation of said body member and said well member, saidapparatus containing pressure fluid port means'in fluid communication onone end with the actuating means in said body member with the otherendextending through the wall of said body member and adapted tocommunicate with a source of pressure fluid.

3. An apparatus for facilitating underwater wellhead operations which inassembly comprises a verticallyprojecting tubular well fitting, ablowout preventer adapted to be mounted on the upper end of said tubularwell fitting, a blowout preventer lockdown apparatus secured to each ofthe upper and lower ends of said blowout preventer coaxial with the boretherethrough, each said lockdown apparatus comprising a cylindrical bodymember having an axial bore therethrough and being of a size to fit intothe open end of said vertically-arranged tubular well fitting, outwardlyextending shoulder means formed on the outside of said body member, saidshoulder means having a diameter greater than that of at least a portionof the bore of said tubular well fitting in which it fits, locking meanscarried by said body member and being bodily movable outwardly thereofso that a portion of said locking means projects beyond the surface ofsaid body member toward and into contact with seatingtgroove means ininner surface of said well fitting, and actuating means carried by saidbody member for operatively engaging said locking means, said actuatingmeans being movable with respect to said body member in response tofluid pressure application thereto, apparatus containing pressure fluidport means in fluid communication on one end with the actuating means insaid body member with the other end extending through the wall of saidbody member and adapted to communicate with a source of pressure fluid.

4. An apparatus for facilitating underwater Wellhead operations which inassembly comprises a vertically projecting tubular well member, ablowout preventer adapted to be mounted on the upper end of said tubularwell member, lockdown apparatuses secured to the'top and axial boretherethrough and being of a size to fit into the open lower end of avertically-disposed well member, outwardly extending shoulder meansformed on the. out side of each of said body members,"said shouldermeanshaving a diameter greater than that of at least aseating portion of thebore of said tubular well member, locking means carried by each of saidbody members and being bodily movable outwardly thereof so that aportion of said locking means projects beyond the surface of said bodymember toward and into contact with seating groove means in innersurface of said well member, and actuating means carried by each of saidbody members for operatively engaging said locking means, said actuatingmeans being movable with respect to said body member in response tofluid pressure application thereto to move said locking means outwardlyof said body into locking position with a surrounding well memberthereby preventing separation of said body member and said well member,said apparatus f containing pressure fluid port means in fluidcommunication on one end with the actuating means in said body memberwith the other end extending through the; wall of said body member andadapted to communicate with a source of pressure fluid.

References Cited by the Examiner UNITED STATES PATENTS 2,862,560v 12/58Bostock et al 166-217 X 2,906,500; 9/59 Knapp et a1; '166-66.5 2,976,9313/61 Dafiin Q. 166217 X 2,988,144 6/61 Conrad 16666.5 X 3,002,565 10/61Moore 166-217 3,032,125 5/62 Hiser et a1 l6666.'5 X

E. QCONNELL, Primary Examiner,

1. AN APPARATUS FOR FACILITATING UNDERWATER WELLHEAD OPERATIONS WHICH INASSEMBLY COMPRISES A VERTICALLY PROJECTING TUBULAR WELL MEMBER, ABLOWOUT PREVENTER ADAPTED TO BE MOUNTED ON THE UPPER END OF SAID TUBULARWELL MEMBER, A BLOWOUT PREVENTER LOCK-DOWN APPARATUS SECURED TO AT LEASTONE END OF SAID BLOWOUT PREVENTER COAXIAL THEREWITH, SAID LOCK-DOWNAPPARATUS COMPRISING A CYLINDRICAL BODY MEMBER HAVING AN AXIAL BORETHERETHROUGH AND BEING OF A SIZE TO FIT INTO THE OPEN UPPER END OF SAIDVERTICALLY PROJECTING TUBULAR WELL MEMBER, OUTWARDLY EXTENDING SHOULDERMEANS FORMED ON THE OUTSIDE OF SAID BODY MEMBER, SAID SHOULDER MEANSHAVING A DIAMETER GREATER THAN THAT OF AT LEAST A PORTION OF THE BORE OFSAID TUBULAR WELL MEMBER IN WHICH IT FITS, LOCKING MEANS MOVABLY CARRIEDBY SAID BODY MEMBER AND BEING BODILY MOVABLE OUTWARDLY THEREOF SO THAT APORTION OF SAID LOCKING MEANS PROJECTS BEYOND THE SURFACE OF SAID BODYMEMBER TOWARD AND INTO CONTACT WITH SEATING GROOVE MEANS IN THE INNERSURFACE OF SAID WELL MEMBER, ANNULAR SEAL MEANS CARRIED OUTWARDLY ONSAID BODY MEMBER ADAPTED TO FORM A FLUIDTIGHT SEAL WITH A SURROUNDINGWELL MEMBER, AND ACTUATING MEANS CARRIED BY SAID BODY MEMBER ADAPTEDOPERATIVELY ENGAGING SAID LOCKING MEANS, SAID ACTUATING MEANS BEINGMOVABLE WITH RESPECT TO SAID BODY MEMBER IN RESPONSE TO FLUID PRESSUREAPPLICATION THERETO TO MOVE SAID LOCKING MEAN OUTWARDLY OF SAID BODYMEMBER INTO LOCKING POSITION WITH A SURROUNDING WELL MEMBER THEREBYPREVENTING SEPARATION OF SAID BODY MEMBER AND SAID WELL MEMBER, SAIDAPPARATUS CONTAINING PRESSURE FLUID PORT MEANS IN FLUID COMMUNICATION ONONE END WITH THE ACTUATING MEANS IN SAID BODY MEMBER WITH THE OTHER ENDEXTENDING THROUGH THE WALL OF SAID BODY MEMBER AND ADAPTED TOCOMMUNICATE WITH A SOURCE OF PRESSURE FLUID.